Revolving chair



0. 0. KRABOL.

REVOLVING CHAIR.

APPLICATION FILED Ammo` I9I9.

3. ,332,402. Patented Mar. 2, 1920.

OLA'US O. KRABOL, 0F CHICAGO, ILLINOIS.

, .REVOLVING CHAIR.

Specification of Letters Patent.

Patented Mar. 2, 1920.

Application filed August 30, 1919. Serial No. 320,849.

To all whom t may concern:

Be it known that I, CLAUS O. KnABoL, a citizen of the United States, and resident of Chicago, county of Cook, and State of Illinois, have invented certain new and use ful Improvements in Revolving Chairs, of which the following is a specilication, and which are illustrated in the accompanying drawings, forming a part thereof.

The invention relates to revolving chairs and has for an object the provision of means for connecting the legs of such a chair and means for reception of the revolving portion of the chair.

An illustrative embodiment of the invention is shown in the drawings in which;

Figure 1 is a side view, partly broken away, of the base of a revolving chair ernbodying the invention;

Fig. 2 is a section on line 2-2 of Fig. 1;

Fig. 3 is a perspective view of one of the plates utilized, with a second plate shown in dotted lines;

Fig. f1 is a perspective view of an end of a lefr;

7:Fig 5 is a section on line 5-5 of Fig. 2;

Fig. 6 is a plan view of a bottom plate;

Fig. 7 is a plan view of a modified form of top plate;

Fig. 8 is a perspective view of a bushing used with the form of top plate 0f Fig. 7;

Fig. 9 is a side view of a form of button which may be used.

To hold the chair legs, as 10, in assembled relation a central frame, as 11, shown as of the form of a box with a pair of projections, as 12, standing out from each side may be utilized. The frame 11 may be readily formed of four plates, as 13, one of which is Shown in perspective in Fig. 3.

The plate 13 is shown as formed with flanges 14 and 15 at opposite edges and with slots 16, 17 extending froml one end, one half the length of the plate. The frame 11 seen in cross-section in Fig. 2 will result if two plates 11 be assembled with their flanges 14 and 15 facing each other and slots 16 in the same relative position, and if two other plates with flanges 15 and 16 likewise facing each other, but with the slots opposed to those of the firstenamed pair, be slid together in the manner indicated in dotted lines in Fig. 3. When the frame has been thus assembled the edges of the slots may be joined to the sides of the plates, as

by electricvwelding if desired, although it will doubtless be amply strong for all practical purposes without being so secured.

To enable the legs 10 to be assembled with the frame 1l, each leg is formed of a thickness equal to the distance between slots 16 which will be the distance between the projections 12. To receive the flanges 14 and 15, each leg is formed with a pair of grooves, as 17, parallel with the end of the leg and spaced therefrom a distance equal to the spacing of flanges 14: and 15 from slots. 16. This groove may and preferably will be merely a kerf produced by a circular saw.

With the legs and frame formed as described it is only necessary to slide the legs and frame together into the relation shown in Fig. 2 to produce a very strong and neat assembly of the chair base.

j To receive the threaded spider, as 18 which is of the usual form for carrying the screw spindle 19 for adjusting the height of the chair,- a plate, as 20, is shown. This plate may be of cast metal and when so formed preferably has a sleeve, as 21, cast integral therewith. For reception of cover strips, as 22, preferably utilized to enhance the appearance of the chair, the plate 20, is shown as cast with a depending peripherallange, las at 23, under which the cover strips 22 may be confined.

j To act as an abutment for the portions at the ends of plates 13 adjacent the slots 16 tending to prevent said portions from being bent outwardly, the plate 20, is shown as cast with triangular lugs or bosses, as 245, which fit into the corners between projections 12.

The plate 2O may be secured to the legs 10 by screws, as at 25 if desired. The tops of legs 10 may be grooved, as at 26, for reception of the rim 23, or the rim may be cut away to fit over the legs or it may be left intact to rest on top of the same. In any case the bosses 211 are preferably made deeper at their inner corners than the rim.

To carry the set screw, as 27, plate 20 is shown as cast with an upstanding lug 28 provided with a screw threaded perforation 29. The screw 27 is shown as turned into this perforation and projecting over the usual collar 30, on the spider to prevent separation of the chair and base.

As a covering for the lower end of the frame 11 and to prevent endwiee movement of the legs in the frame a bottom cover plate, as 31, shown as formed of a metal stamping may be provided. When a stamped metal plate is utilized the plate preferably has portions, as 32, struck out from the metal of the plate to perform the function of the bosses 24, as described in connection with plate 20, and a peripheral flange, as 33, corresponding with iiange 23 of plate 20, to take the lower ends of cover strips 22. The rim 33 of plate 31 is shown as interrupted at the `locations for legs 10, the metal of the plate at these points being extended into ears as 34, perforated, as at 35', to receive screws, as 3,6,V to secure the plate in place.l The bushing or sleeve 21 is preferably of such a length and size as to project slightly, as at 37 through an opening, as 38, in the center of the bottom cover plate. rllhis arrangement assists in steadying the sleeve in resisting lateral pressures of screw spinolle 19.

A modification of the top cover plate is illustrated in Fig. 7 comprising a metall stamping, as 39, which is in all respects similar to plate 31 with the exception of the omission of ears 34, the peripheral rim being made continuous at those points and screw holes 40 being providedV for the screws 25. With this form of plate the sleeve 0.1 bushing for spindle 19 is provided in the form of a piece of pipe, as 41, Fig. 8 which may be loosely placed in the center of frame 11. Pipe 41 may have a shoulder, as 42, to seat against the lower plate 31the reduced end 43 thus formed being adapted to project through the bottom plate in the manner indicated at 37 in connection with sleeve 21.

When the modication of Figs. 7 and 8 is used a substitute for lug 28 and screw 27 in the form of a button, as 44, Fig. 9 may be provided, which button may be revolubly secured to plate` 39, as by a rivet 45'. The button may be turned to one side for placing of spider 18 and then by means of a hammer and punch may be turned so that its lip 46 will overlie the collar 30.

I claim as my invention- 1. Means for connecting the legs of a revolving chair comprising, in combination, a boX-like central portion, parallel projections at each side of said portion spaced apart to receive the legs of a chair, and means to secure each projection to a chair leg, each of said means integral with its projection.

' 2. Means for connecting the legs of a revolving chair comprising, in combination, a

box-like central portion, parallel projections at each side of said portion spaced apart to receive the legs of a chair, and means integral with and protruding inwardly from each projection adapted to seat in a groove in the side of a chair leg.

3. Means for connecting the legs of a reieaaos volving chair comprising, in combination, a box-like central portion, parallel projections at each side of said portion at the corners thereof spaced to receive the legs of a chair, and means to secure each projection to a chair leg, each of said means integral with its projection.

4. Means for connecting the legs of a revolving chair comprising a plurality of plates slotted and interitted to form a boxlilre central portion, parallel projecting portions at each side thereof,y and means for securing said projections to the chair legs.

5. In means for connecting the legs of a revolving chair, in combination, a box-like central portion having spaced projections from each side at they corners thereof, said portion and projections comprising a plurality of metal plates slotted and interfitted,

and means for securing the chair legs be-f tween said projections.

6. In means for connecting the legs of a revolving chair, in combination, a box-like central portion having spaced projections from each side at the corners` thereof, said portion and projections comprising a, plurality of like metal plates slotted and interitted, and means for securing the chair legs between said projections, i

7. In. means for connecting the legs of a revolving chair, in combination, a box-like central portion, parallel projecting portions at each side at the corners of saidcentral portion, said projections comprising continuations of the sides of the central portion beyond its corners, inwardly projecting iianges at the edges of said projecting portions, said projections adapted to receiveplates. projecting from each side thereof,l

inwardly directed angular portions carried by said plates, .legslying between said plates and provided with grooves for the reception of said portions, centrally perforated top and bottom cover plates coverlng the junction of said legs and frame,l said plates secured to the legs, projections on said plates lying in the cornersbetween said projecting plates, a sleeve lying in said frame extending from said top cover plate to and through said bottom cover plate for reception of a chair spindle.

l0. In a revolving chair base, in combination, a central 'frame and leg receiving projections formed of metal stampings, legs secured to said projections, top and bottom cover plates for said frame comprising metal stampings centrally perforated for reception of a chair spindle, the upper cover plate adapted to support the spider of a spindle, a button revolubly secured to said top cover plate, adapted to be turned to overlie the usual collar of a spider.

11. A plate adapted to be assembled with a plurality of other like plates to connect the legs of a chair, comprising a rectangular body portion having spaced slots eX- tending throughout one half its extent rom one end, flanges turned toward the same side of the plate from opposite edges of the plate and parallel with said slots.

l2. A plate adapted to be assembled With a plurality of other like plates to connect the legs of a chair, comprising a substantially rectangular body portion having spaced slots extending throughout one-half its extent from one end, portions of the plate lying between each slot and the margin of the plate parallel thereto projecting out of and in the same direction from a plane including both said slots, whereby when said plate is assembled with other like plates, chair legs may be gripped by said projecting portions.

CLAUS O. KRABOL. 

